Same employer, new client within 20 miles, does employer need to file H1B amendment

[BruceW]

I got assigned from client A to Client B, both work locations about 20 miles apart and within same MSA. My job designation and employer are still the same and pay is very slightly affected, but still well above the prevailing wage rate. My employer's visa dept determined that H1B amendment is not required to be filed.

My employer is very reputed and one of the biggest IT service company. Its visa department determined that my assignment to new client does not require H1 amendment. I would like to believe my company's visa dept has come to be very diligent about following the visa rules in last couple of yrs. Upon my inquiry, they have reconfirmed that visa amendment is not required since work locations are only 20 miles apart. However, I find this puzzling, since there is a client change involved.

My questions are:

1. Is H1B amendment really required to be filed in my case? 

2. If not, then how will USCIS come to know about my new work location? What happens if they decide to physically audit my work location?

3. Can this affect my H1B extension in any way? For eg., how can I be extending H1B for client B (due later in 2019), when USCIS did not know about it?

 

Should I be concerned? Please help?